Crankcase ventilation system and apparatus



' D. G. Roos 2,407,178

Filed oet. 15', 1945 2 sheets-sheet '1f Sept. 3, 1946.

` cnANKcAsE VENTILATION SYSTEM Ann APPARATUS D. G. Roos 2,407,178

APPARATUS cRANKcAsE vENT1LAT1oN"-VsYsTEM AND Filed om. 15, i943 `sheets-S113 2 IN VEN TOR. elmar (i R00:

Aments per se;

.be preferred, in. which: 1

Patented Sept. 3, 1946 CRANKCASE VENTILATION SYSTEM AND i APPARATUS i Delmar G. Roos, Toledo, Ohio,

assignor to Willys- Overland Motors, Inc.,To ledo, Ohio, a corporation of Delaware Application October 15, 1943, Serial No. 4506,453

'I'his invention relates to a system and apparatusfor circulating a current of air through a crankcase of aninternal combustion engine especially for the purpose ofremoving vapors and gases from the crankcase and valve mechanism chamber of the engine'.A l i The invention ccmprehends a system and apparatus for continuouslyremoving vapors from the crankcase `during engine operation whereby oil contamination by dilution as well as by sludge formation due to oxidation is materially reduced. One of `the principal objectsof the invention is the provision of means-interealated with the air cleaner and conduit for conveying air to the carburetor as to divert a portion of the air from the air cleaner throughthe crankcase and valve push rod chamber,` so that clean air flows through the crankcase and valve push rod chamber.

Another object of the invention `resides in the provision of a systemandapparatus for circulating acurrent of clean air` through the crankcase and whereby. the air passing through' the crankcaseand valve push rod compartment is discharged into the intake manifold ofthe internal combustion engine.` c I Another object of the invention is the provision of a crankcase Ventilating system whereby a` portionjof the clean air which would otherwise normallyapass `through thefcarbu'reto'r is diverted throughy the engine crankcase and `incorporating means for varying the rate of flow of'air through the crankcase dependent upon the speed ofthe engine.

Another object of the invention is thev provision ofmeans for circulating a current of clean air throughthe crankcase of an internal combustion engine which arrangement may be adapted to existing engine types without the necessity of material alterations being made in the engine structure. v

Still a further object of the invention is the Aprovision of a system of circulating air through a crankcase-whereby the circulating air and entrained vapors" are discharged into the intake manifold of the engine. V

Further objects and advantages are within the scope of this invention such as relate to the arrangementoperation and function of the related elementsofV the structure, to various details of construction and to combinations of parts, eleand to economies of manufacture and numerous other features as will be apparent from a consideration of the'specification `and l awings -of a form of the invention,

which may 3 Claims. (C1. 123%119) l22 held in place by a bolt 23.

Figurei 1 is an end elevational view of an internal combustion engine, parts being shown in section illustrating the system and apparatus of my invention; 1 `l i Figure 2 is a top plan view of the engine and associated apparatus shown in Figure 1;

Figure 3 is a view taken substantiallyon the line 3.--3 of Figure 2 `with the air cleaning arrangement shown partially in section;

"Figure 4 is an enlargeddetailed sectional view taken substantially on the line, d--II of Figure l;

Figure 5 is a detailed sectional View taken substantially on the line 5-5 of Figure 2.

While I have illustrated a form of my invention asincorporated in a multi cylinder engine of alcharacter usable in an automotive vehicle, it is to be understood that I contemplate the utilization of my invention with any type of engine wherein the same may be found to have utility.

Referring to the drawings in detail, I have illustrated a` conventional type of internal combustion engine inclusive of a erankcase I0 mounted up'on suitable support I I one or more cylinders I2, each cylinder accommodating areciprocating piston I3 connected by means of a connecting rod I4 to a crankshaft I5, the latter being journaled for rotation in suitable bearings carried bythe crankcase Il);` The lower portion of the crankcase is closed by means of an oil pan or reservoir I6. 'I'he upper portion of the crankcase is formed with a valve push rod chamber I1, the valve push rods|8 being arranged-in bearings I9 and are actuated by suitable camshaft 2U. The chamber I'I is provided in its side wall with opening 2| which is covered by means of a closure or fitting The valve push rod chamber I'I is in communication with the crankcase by means of a passageway 25.

Secured to the engine block is an intake manifold 21 which is connected to a fuel and air mixing device or carburetor 28 for supplying a combustible mixture to the engine, the latter being provided with a conventional exhaust manifold (not shown). Connected to the carburetor 28 is an air horn 30 which communicates with an air cleaner 3| by means of a duct or conduit 32 secured to the air horn by means of a clamp 33, the other end of the tube 32 being connected to the air cleaner-'by means of a flexible conduit or tube 34. The air cleaner 3l is inclusive of a substantially cylindrical chamber which is closed at its lower end by means of a cup-like member 31 which is adapted to containa small quantity of liquid 38 as for example, oil. or 'the like, to trap particles removed from the air entering the cleaner. The member 31 is retained in position by clamping means 36. The upper portion of the cleaner is provided with a series of louvered inlets 33 to facilitate the ingress of air into the interior of the cleaner. The air cleaner structure is provided with projections40 which engage brackets 4l secured to the dash board 42 or other suitable portion of the vehicle, the projections 40 being secured to brackets 4I by means of Wing nuts 43 or other suitable retaining means.

Vertically arranged With respect to the engine block and projecting into th'e crankcase I6 is an oil ller tube 45 preferablyfabricatedof sheet metal tubing. The upper portionof the tube 45 is provided with a tting 46 of flared or frustoconical configuration to facilitate'the'introduction of lubricant or oil into the engine crankcase.

The fitting 46 is tightly closed by means of acap` 41 through the medium of a sealing gasket 44 urged into sealing position under'. the influence of a spring '50, as particularlyshown in Figure 5. Secured to the cap 41 isa rod 46 which extends downwardly through the tube 45 into theoil pan I6 and provides a means for. measuring or'determining the'oil level in the oil pan i6. rJhe cap 41 is provided exteriorly with a member 48a` having upturned ear portions 49 affordingfa manipulating means for removing the oil ller `cap! 41, when it4 becomes necessary lto introduce lubricant. into the filler tube. It is `desirable that the entrance to the ller tube be' tightly closed in order that `all air taken into the crankcase for ventilatlon'pur poses be admitted throughthe air cleaner 3 l The conduit `32 is provided with a branch pasy.

sageway vand the aredtting 46 of the oil filler system is provided with a laterallybextending tube or passageway 52 which'are joined together by means of a flexibletube 53 heldin place by clamps 54. The tubes or passageways 5I, 52 and 53 form an air passage or ductv from the'conduit 32 to the oil ller tube 45 thus providing ameans for diverting a portion of the air taken in through the air cleaner 3| into the oil filler tube 45 thence into the crankcase I5.

The fitting 22` closing the opening `2|! in the wall of the valve push rod chamberisprovided with an L-shaped fitting 56 to which connected a tube 51 leading to another L-shaped f1tting58 which has'a threaded tenon portion 56 engaging in a threaded opening in a member 66. The-member 60 is formed with atenon .6| which ,engages in an interior threaded portionina sleeve 62,

vthe latter having a `portion 63 `engaging in a threaded opening in a wall of the intake manifold 21. The sleeve 62 is'formed interiorly withvalve chamber 65 in which is positioned .areciprocable valve or airflow regulating member 66. The valve member 66 is provided with a chamberl 61 which communicates with the intake manifold through a passageway or metered opening 68. The walls of the chamber 61 are formed with transversely arranged passageways 69 which open into the chamber 65. The valve'member 66 is normally urged into engagement with the endA of thetenon 6| underthe influence of 4an expansive coil spring 16. The valve member 66 is formed with a frustoconical wall portion 12 which is adapted toseat against a shoulder Aor abutment 13 formed in the interior passageway in the tenon portion 63 of sleeve 62. When the valve member 66 moves in a left-hand direction asviewed in Figurel, the

vtapered seat 12 engages the abutment 13 sothat mthereafter air may only circulate through the metered passageway 68;

nor Vduct formed by tubes 5I, 52 and 53 into the oil filler tube 45, the air passing into the crank- 4case throughpassageway 25, valve push rod compartment; |-1,"thence through fitting 56, tube 51, lfitting 58, member 60 and sleeve 62 into the inta-ke manifold ofthe engine and below the carburetor 28. When the engine is operating at comparatively slow speed, that is, when the sub-atmospheric pressure in the intake manifold is only slightly less than atmospheric pressure, theA valve member 66 is inthe position showninI Figure 4, the air circulatingthrough theacrankcase'passing from chamber 61 through the openin'gsldand past the valve seat 12 into the intakefmanifold as well as through the metered passageway. When the engine .speed increases., .the ypressure in the intake .manifoldis further reducedtcreating .a higher vacuum therein. The. air pressure in the crankcase and valve .chamberl 65.bein'g:substan tiallfy greater than thepressure in fthe intake manifold, overcomes the ypressure of the spring 10 and causes the valve 66 to move ina leftrhand direction until the taperedseat 12 engages the abutment 13, so that the only air passageway through the valve is by means of themetered opening or pasasge 68. With the valve in `closed position, the rate of `flow vof air through Athe passage 68 may be comparatively high with' increased engine speed, but the kamount 'of air :circulating through the crankcase will remain within practical limits, although variable,as itis dependent upon theengine'speed` and the position-'of `the valve member 66. In thispmanner'the circulation of air through the crankcase isy controlled or regulated so that at high enginezspeedsithe circulation 'of air is not'increased to a'point which would carry out oil from the crankcase. It should 'also be noted that all of the air circulating through the crankcase together with the fumes andother vaporsentrainedby theainare discharged into theuintakemanifold and into the engine, being subsequently discharged through the engine exhaust system.

.It is apparentfthat, within therscope of the invention, modifications and ydifferent arrangements may be made other'than is herein .disclosed, and the present disclosure is illustrative merely, the invention comprehending `all variations thereof.

What I claim is:

l. In combination, an. arrangement for ventilating the crankcase of an internal combustion engine havingv an intake manifold anda plurality of cylinders in line and an adjacent valve chamber, a carburetor, an oil filler tube extending into said crankcase substantially below'the lower end and opposite the valve chamber vand projecting above the engine; an air cleaner, an air conduit connectedto said carbureton'means connecting said air cleaner and'said'air conduit, a closure for sealing the upper end of said filler tube, means establishing communication between theupperportion of said llerltube and said'air conduit, and means includingfa connectionbeengine having an intake manifold and a plurality of cylinders in line and an adjacent valve chamber, a carburetor, an oil iiller tube extending into said crankcase, substantially below the lower end and opposite the valve chamber and projecting above the engine; an air cleaner, an

air conduit connected to said carburetor, meansY connecting said air cleaner and-said air conduit,

a closurevfor sealing the upper end of said llerr the valve chamber and intake manifold, said valve means being dependent for actuation upon tube, means establishing communication between the upper portion of said filler tube and said air conduit, means including a connection between the valve chamber and the intake manifold'v whereby the reduced pressure in said intake man-` ifold sets up a ow of filtered air from said air cleaner through said filler tube and crankcase, and spring loaded valve means positioned exteriorly of the engine in the connection between the amplitude of subatmospheric pressure in the intake manifold for regulating the amount of air flowing through the crankcase.

3. In combination, an internal combustion engine having a series of vertical cylinders arranged in a line, and a crank case below the cylinders, a valve chamber laterally disposed to the cylinders, a carburetor having an intake and an outlet, an oil ller tube projecting from above the engine and extending into the crankcase below the valve chamber and on the opposite side of the cylinders from the said chamber, an air cleaner on the same side of the engine as the filler tube, means connecting the carburetorsV intake with said air cleaner, an air conduit connected to said ller tube, means connecting the air cleaner and said air conduit, a closure for sealing the upper end of the ller tube, an intake manifold connected to the carburetors outlet, and valve means connecting the valve chamber and the intake manifold.

DELMAR G. ROOS. 

